The background description provided herein is for the purpose of generally presenting the context of the disclosure. Work of the presently named inventors, to the extent it is described in this background section, as well as aspects of the description that may not otherwise qualify as prior art at the time of filing, are neither expressly nor impliedly admitted as prior art against the present disclosure.
Many mobile devices include global positioning system (GPS) receivers or other positioning technologies that allow the devices to determine the geographic coordinates of the mobile devices. These positioning technologies enable the mobile devices to serve as navigation devices, in some cases providing turn-by-turn driving directions to a mobile device user. Most navigation devices present a georeferenced map to the mobile device user to allow the mobile device user to see on the map the current location of the mobile device. In many devices, the map data is stored on a memory in the mobile device. In some cases, the map data may occupy hundreds megabytes or over a gigabyte of storage.
Recently, many mobile devices operating as navigation devices have been configured to download map data as needed, thereby reducing the amount of storage space needed for map data. However, mobile devices so configured require data connections to download the map data. To reduce the amount of data downloaded, the mobile devices are typically configured to download map data for areas local to the mobile device. As the mobile device moves, the mobile device may be configured to access a data network and download new map data corresponding to the area local to the new location of the mobile device.
However, mobile devices sometimes may encounter geographic areas of limited or no mobile data network access. Further, mobile devices may enter geographic areas in which access to a data network may be slower or faster than in other areas. Still further, mobile devices may enter areas in which access to a data network is more expensive or less expensive than in other areas.